Objective To investigate the impacts of cytokines （interleukin-4，IL-4；tumor necrosis factor-α，TNF-α） and medications of bronchial asthma （dexamethasone，aminophylline，salbutamol） on the activity of histamine N-methyltransferase（HMT） in tracheal epithelial cells.Methods BEAS-2B bronchial epithelial cells were cultured and treated with different concentration of TNF-α, IL-4, dexamethasone, salbutamol and aminophylline respectively. The activity of HMT in BEAS-2B cells was determined by high performance liquid chromatography.Results The activity of HMT in tracheal epithelial cells was (50±7) pmol?min-1?mg pro-1.TNF-α and IL-4 lowered the activity of HMT significantly at the concentration equal to or higher than 1 ng/mL and 5 ng/mL respectively，and reached the maximum inhibitory effect at the level of 10 ng/mL.Dexamethasone and aminophylline could ameliorate distinctly the inhibitory effect of TNF-α on the activity of HMT, while salbutamol had no significant inhibitory effect.Conclusions TNF-α and IL-4 exert the lowering effect on the activity of HMT，which would be one important cause of airway hyperreactivity.Glucocorticoids and theophyllines are administered to treat asthma partly due to its relieving mechanism of TNF-α negative effects on HMT.
ObjectiveTo explore the influence of propofol as well as sevoflurane on the histamine release induced by mivacurium chloride. MethodsForty patients with American Sociaty of Anesthesiologists stage Ⅰ-Ⅱ scheduled to receive ear-nose-throat surgery between March and October 2012 were recruited and were randomly assigned into two groups:propofol group and sevoflurane group. Patients in the propofol group were induced with targeted intravenous infusion with propofol. Patients in the sevoflurane group was induced with sevoflurane. The blood specimen was prepared before mivacurium chloride (0.16 mg/kg) infusion (T0), 1 minute (T1), 3 minutes (T2), and 5 minutes (T3) after the infusion. Mean blood pressure (MBP) and heart rate (HR) were recorded at corresponding time points. In addition, we recorded the symptoms of anaphylactic reaction such as skin erythema or bronchospasm. ResultsBoth MBP and HR decreased after anesthesia induction. However, there was no significant difference from that before the induction in both groups, and no difference was found between the two groups (P>0.05). The concentration of histamine in both groups at T1 and T2 was significantly higher than that at T0 (P<0.05). The concentration of histamine in both groups at T4 was significantly higher than that at T0 (P<0.05). The concentration of histamine in the propofol group was higher than that in the sevoflurane group. No skin erythema or bronchospasm was found in any of the two groups. ConclusionMivacurium chloride at a dose of 0.16 mg/kg can be safely used in propofol anesthesia, as well as sevofluane anesthesia, with no clinically significant histamine release or adverse hemodynamic fluctuation.
ObjectiveTo evaluate the association between H2RA and the risk of hip fracture by performing a meta-analysis. MethodsWe searched CNKI, PubMed and EMbase from inception to September 19th 2016, to collect case-control studies or cohort studies reporting the risk of hip fracture with H2RA. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then meta-analysis was performed using Stata 13 software. ResultsEleven studies involving 206 276 hip fracture cases were included. The result of meta-analysis showed that patients receiving H2RA therapy had approximately 1.12 times the risk of developing hip fracture compared with nonusers (OR=1.12 95%CI 1.02 to 1.24, P=0.022). Subgroup analyses by interval time indicated that the risk appeared greater with the continuous users (OR=1.11, 95%CI 1.01 to 1.24, P=0.039) whereas the discontinuous users was not significantly associated with hip fracture risk. ConclusionH2RA therapy may be associated with an increased risk of hip fracture. For patients with intermittent medication, the side effect may disappear by discontinuation of PPI use for at least 30 days, but the study did not find time-effect relationship or dose-effect relationship. Considering the limitations of this study, more rigorous clinical trials evaluating the potential side-effect of H2RA are needed.